Electromagnetic injector for an I.C. engine

Abstract

The electroinjector according to the invention is provided with a small tubular armature, whose bottom wall is constituted by a plate, of material which resists deformation due to impact and directly fastened on to the cylindrical side wall of the same armature, with which a shutter of an injection nozzle is fixedly secured.

We claim: 
     
       1. Electroinjector for an I.C. engine, said electroinjector comprising a core of ferromagnetic material, a coil surrounding the core, an injection nozzle, a small tubular movable armature positioned between the core and the injection nozzle and being coaxial with both said core and said injection nozzle, a return spring pushing the small armature towards said injection nozzle, a tube, partly inserted inside the core, acting as inner guide for the small armature, a duct for delivering the fuel towards the injection nozzle, an outer shell closing the magnetic circuit together with the core and the small armature, and there being a plate and a shutter, the electroinjector being characterized in that the small armature is provided with an end wall constituted by said plate with said plate being formed of material resistant to deformation due to impact, and directly fastened on to the cylindrical side wall of the small armature independently of said shutter, and said shutter being made of sealing material and fixedly secured directly to said plate separate and apart from said armature. 
     
     
       2. Electroinjector according to claim 1, characterized in that said plate is constrained to the cylindrical side wall of the small armature by means of at least two radial projections provided on the cylindrical wall by notching said cylindrical wall radially inwardly beneath said plate. 
     
     
       3. Electroinjector according to claim 2, characterized in that an end of the cylindrical side wall of the small armature disposed adjacent said injection nozzle is provided with a collar of reduced thickness, ending with an annular shoulder against which said plate is housed. 
     
     
       4. Electroinjector according to claim 1, characterized in that said plate is shaped in washer form. 
     
     
       5. Electroinjector according to claim 4, characterized in that said shutter is fastened to said washer by riveting. 
     
     
       6. Electroinjector according to claim 1, characterized in that said plate has a frustoconical shape. 
     
     
       7. Electroinjector according to claim 6, characterized in that said shutter is fastened on to said plate of frustoconical shape by riveting. 
     
     
       8. Electroinjector according to claim 1, characterized in that said shutter is fastened on to said plate by riveting.